docs: def stream(self):
          """
          A view function that streams server-sent events. Ignores any
          :mailheader:`Last-Event-ID` headers in the HTTP request.
          Use a "channel" query parameter to stream events from a different
          channel than the default channel (which is "sse").
          """
          channel = request.args.get('channel') or 'sse'
  
          @stream_with_context
          def generator():
              for message in self.messages(channel=channel):
                  yield str(message)
  
          return current_app.response_class(
              generator(),
              mimetype='text/event-stream',
          )